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BUG: KASAN: use-after-free in decode_session6 net/xfrm/xfrm_policy.c:3393 [inline]
BUG: KASAN: use-after-free in __xfrm_decode_session+0x1cfb/0x2e90 net/xfrm/xfrm_policy.c:3485
Read of size 1 at addr ffff88809166e75e by task syz-executor.3/13510
CPU: 1 PID: 13510 Comm: syz-executor.3 Not tainted 5.5.0-rc2-next-20191220-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x197/0x210 lib/dump_stack.c:118
print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
__kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
kasan_report+0x12/0x20 mm/kasan/common.c:639
__asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132
decode_session6 net/xfrm/xfrm_policy.c:3393 [inline]
__xfrm_decode_session+0x1cfb/0x2e90 net/xfrm/xfrm_policy.c:3485
xfrm_decode_session include/net/xfrm.h:1138 [inline]
vti_tunnel_xmit+0x277/0x17e0 net/ipv4/ip_vti.c:269
__netdev_start_xmit include/linux/netdevice.h:4450 [inline]
netdev_start_xmit include/linux/netdevice.h:4464 [inline]
xmit_one net/core/dev.c:3420 [inline]
dev_hard_start_xmit+0x1a3/0x9b0 net/core/dev.c:3436
sch_direct_xmit+0x372/0xd30 net/sched/sch_generic.c:313
qdisc_restart net/sched/sch_generic.c:376 [inline]
__qdisc_run+0x4bf/0x1770 net/sched/sch_generic.c:384
__dev_xmit_skb net/core/dev.c:3677 [inline]
__dev_queue_xmit+0x1650/0x35c0 net/core/dev.c:3982
dev_queue_xmit+0x18/0x20 net/core/dev.c:4046
neigh_direct_output+0x16/0x20 net/core/neighbour.c:1527
neigh_output include/net/neighbour.h:510 [inline]
ip6_finish_output2+0x109a/0x25c0 net/ipv6/ip6_output.c:116
__ip6_finish_output+0x444/0xaa0 net/ipv6/ip6_output.c:142
ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152
NF_HOOK_COND include/linux/netfilter.h:296 [inline]
ip6_output+0x25e/0x880 net/ipv6/ip6_output.c:175
dst_output include/net/dst.h:436 [inline]
ip6_local_out+0xbb/0x1b0 net/ipv6/output_core.c:179
ip6_send_skb+0xbb/0x350 net/ipv6/ip6_output.c:1795
udp_v6_send_skb.isra.0+0x7b0/0x15b0 net/ipv6/udp.c:1173
udpv6_sendmsg+0x22f3/0x2b30 net/ipv6/udp.c:1471
inet6_sendmsg+0x9e/0xe0 net/ipv6/af_inet6.c:576
sock_sendmsg_nosec net/socket.c:643 [inline]
sock_sendmsg+0xd7/0x130 net/socket.c:663
____sys_sendmsg+0x358/0x880 net/socket.c:2342
___sys_sendmsg+0x100/0x170 net/socket.c:2396
__sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2486
__do_sys_sendmmsg net/socket.c:2515 [inline]
__se_sys_sendmmsg net/socket.c:2512 [inline]
__x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2512
do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a919
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f160d5e3c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045a919
RDX: 0000000000000066 RSI: 000000002000ac80 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000003e8 R11: 0000000000000246 R12: 00007f160d5e46d4
R13: 00000000004c9267 R14: 00000000004e0fa0 R15: 00000000ffffffff
Allocated by task 9331:
save_stack+0x23/0x90 mm/kasan/common.c:72
set_track mm/kasan/common.c:80 [inline]
__kasan_kmalloc mm/kasan/common.c:513 [inline]
__kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486
kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527
__do_kmalloc_node mm/slab.c:3616 [inline]
__kmalloc_node_track_caller+0x4e/0x70 mm/slab.c:3630
__kmalloc_reserve.isra.0+0x40/0xf0 net/core/skbuff.c:141
__alloc_skb+0x10b/0x5e0 net/core/skbuff.c:209
alloc_skb include/linux/skbuff.h:1049 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:321 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:373 [inline]
nsim_dev_trap_report_work+0x25c/0xaf0 drivers/net/netdevsim/dev.c:412
process_one_work+0x9af/0x1740 kernel/workqueue.c:2264
worker_thread+0x98/0xe40 kernel/workqueue.c:2410
kthread+0x361/0x430 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Freed by task 9331:
save_stack+0x23/0x90 mm/kasan/common.c:72
set_track mm/kasan/common.c:80 [inline]
kasan_set_free_info mm/kasan/common.c:335 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/common.c:474
kasan_slab_free+0xe/0x10 mm/kasan/common.c:483
__cache_free mm/slab.c:3426 [inline]
kfree+0x10a/0x2c0 mm/slab.c:3757
skb_free_head+0x93/0xb0 net/core/skbuff.c:591
skb_release_data+0x613/0x8c0 net/core/skbuff.c:611
skb_release_all+0x4d/0x60 net/core/skbuff.c:665
__kfree_skb net/core/skbuff.c:679 [inline]
consume_skb net/core/skbuff.c:838 [inline]
consume_skb+0xfb/0x410 net/core/skbuff.c:832
nsim_dev_trap_report drivers/net/netdevsim/dev.c:387 [inline]
nsim_dev_trap_report_work+0x7cb/0xaf0 drivers/net/netdevsim/dev.c:412
process_one_work+0x9af/0x1740 kernel/workqueue.c:2264
worker_thread+0x98/0xe40 kernel/workqueue.c:2410
kthread+0x361/0x430 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
The buggy address belongs to the object at ffff88809166e000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1886 bytes inside of
4096-byte region [ffff88809166e000, ffff88809166f000)
The buggy address belongs to the page:
page:ffffea0002459b80 refcount:1 mapcount:0 mapping:ffff8880aa402000 index:0x0 compound_mapcount: 0
raw: 00fffe0000010200 ffffea0002322108 ffffea000138ac88 ffff8880aa402000
raw: 0000000000000000 ffff88809166e000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88809166e600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88809166e680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88809166e700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88809166e780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88809166e800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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